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BACKGROUND: Atherosclerosis is an inflammatory disease. Interleukin 18 (IL-18) is an inflammatory molecule that has been linked to the development of atherosclerosis and cardiovascular disease. OBJECTIVE: To evaluate the possible relationship between plasma levels of IL-18 and the presence of atherosclerosis evaluated at the carotid level, as well as to analyze the possible modulation by different polymorphisms in a Mediterranean population. MATERIAL AND METHODS: Seven hundred and forty-six individuals from the metropolitan area of Valencia were included, recruited over a period of 2 years. Hydrocarbon and lipid metabolism parameters were determined using standard methodology and IL-18 using ELISA. In addition, carotid ultrasound was performed and the genotype of four SNPs related to the IL-18 signaling pathway was analyzed. RESULTS: Patients with higher plasma levels of IL-18 had other associated cardiovascular risk factors. Elevated IL-18 levels were significantly associated with higher carotid IMT and the presence of atheromatous plaques. The genotype with the A allele of the SNP rs2287037 was associated with a higher prevalence of carotid atheromatous plaque. On the contrary, the genotype with the C allele of the SNP rs2293224 was associated with a lower prevalence of atheromatous plaque. CONCLUSIONS: High levels of IL-18 were significantly associated with a higher carotid IMT and the presence of atheromatous plaques, which appear to be influenced by genetic factors, as evidenced by associations between SNPs in the IL-18 receptor gene and the presence of atheroma plaque.
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Doenças das Artérias Carótidas , Espessura Intima-Media Carotídea , Genótipo , Interleucina-18 , Placa Aterosclerótica , Polimorfismo de Nucleotídeo Único , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Alelos , Aterosclerose/genética , Doenças das Artérias Carótidas/genética , Ensaio de Imunoadsorção Enzimática , Fatores de Risco de Doenças Cardíacas , Interleucina-18/genética , Placa Aterosclerótica/genética , Receptores de Interleucina-18/genética , Fatores de Risco , EspanhaRESUMO
The SARS-CoV-2 coronavirus is responsible for the COVID-19 pandemic resulting in a global health emergency. Given its rapid spread and high number of infected individuals, a diagnostic tool for a rapid, simple, and cost-effective detection was essential. In this work, we developed a COVID-19 diagnostic test, that incorporates a human internal control, based on the Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP). When working with synthetic SARS-CoV-2 RNA, the optimized RT-LAMP assay has a sensitivity of 10 viral copies and can be detected by fluorescence in less than 15 min or by the naked eye in 25 min using colorimetric RT-LAMP. To avoid the RNA extraction step, a pre-treatment of the sample was optimized. Subsequently, a validation was performed on 268 trypsin treated samples (including nasopharyngeal, buccal, and nasal exudates) and amplified with colorimetric RT-LAMP to evaluate its sensitivity and specificity in comparison with RT-qPCR of extracted samples. The validation results showed a sensitivity and specificity of 100% for samples with Ct ≤ 30. The rapid, simple, and inexpensive RT-LAMP SARS-CoV-2 extraction-free procedure developed may be an alternative test that could be applied for the detection of SARS-CoV-2 or adapted to detect other viruses present in saliva or nasopharyngeal samples with higher sensitivity and specificity of the antibody test.
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Numerous genes involved in different metabolic diseases have been identified, and this number is increasing [...].
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Oxidative stress (OS) is a relevant intermediate mechanism involved in Type 2 Diabetes Mellitus (T2D) development. To date, the interaction between OS parameters and variations in genes related to T2D has not been analyzed. AIMS: To study the genetic interaction of genes potentially related to OS levels (redox homeostasis, renin-angiotensin-aldosterone system, endoplasmic stress response, dyslipidemia, obesity and metal transport) and OS and T2D risk in a general population from Spain (the Hortega Study) in relation to the risk of suffering from T2D. MATERIALS AND METHODS: One thousand five hundred and two adults from the University Hospital Rio Hortega area were studied and 900 single nucleotide polymorphisms (SNPs) from 272 candidate genes were analyzed. RESULTS: There were no differences in OS levels between cases and controls. Some polymorphisms were associated with T2D and with OS levels. Significant interactions were observed between OS levels and two polymorphisms in relation to T2D presence: rs196904 (ERN1 gene) and rs2410718 (COX7C gene); and between OS levels and haplotypes of the genes: SP2, HFF1A, ILI8R1, EIF2AK2, TXNRD2, PPARA, NDUFS2 and ERN1. CONCLUSIONS: Our results indicate that genetic variations of the studied genes are associated with OS levels and that their interaction with OS parameters may contribute to the risk of developing T2D in the Spanish general population. These data support the importance of analyzing the influence of OS levels and their interaction with genetic variations in order to establish their real impact in T2D risk. Further studies are required to identify the real relevance of interactions between genetic variations and OS levels and the mechanisms involved in them.
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Diabetes Mellitus Tipo 2 , Adulto , Humanos , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Haplótipos , Obesidade/genética , Alelos , Polimorfismo de Nucleotídeo Único , Estudos de Casos e ControlesRESUMO
Copy number variations (CNVs) are a type of genetic variation involving from 50 base pairs (bps) to millions of bps and, in a general point of view, can include alterations of complete chromosomes. As CNVs mean the gain or loss of DNA sequences, their detection requires specific techniques and analysis. We have developed Easy One-Step Amplification and Labeling for CNV Detection (EOSAL-CNV) by fragment analysis in a DNA sequencer. The procedure is based on a single PCR reaction for amplification and labeling of all fragments included. The protocol includes specific primers for the amplification of the regions of interest with a tail in each of the primers (one for forward and another for the reverse primers) together with primers for tail amplification. One of the primers for tail amplification is labeled with a fluorophore, allowing the amplification and labeling in the same reaction. Combination of several tail pairs and labels allows the detection of DNA fragment by different fluorophores and increases the number of fragments that can be analyzed in one reaction. PCR products can be analyzed without any purification on a DNA sequencer for fragment detection and quantification. Finally, simple and easy calculations allow the detection of fragments with deletions or extra copies. The use of EOSAL-CNV allows simplifying and reducing costs in sample analysis for CNV detection.
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Variações do Número de Cópias de DNA , Reação em Cadeia da Polimerase/métodosRESUMO
BACKGROUND: The potential joint influence of metabolites on bone fragility has been rarely evaluated. We assessed the association of plasma metabolic patterns with bone fragility endpoints (primarily, incident osteoporosis-related bone fractures, and, secondarily, bone mineral density BMD) in the Hortega Study participants. Redox balance plays a key role in bone metabolism. We also assessed differential associations in participant subgroups by redox-related metal exposure levels and candidate genetic variants. MATERIAL AND METHODS: In 467 participants older than 50 years from the Hortega Study, a representative sample from a region in Spain, we estimated metabolic principal components (mPC) for 54 plasma metabolites from NMR-spectrometry. Metals biomarkers were measured in plasma by AAS and in urine by HPLC-ICPMS. Redox-related SNPs (N = 341) were measured by oligo-ligation assay. RESULTS: The prospective association with incident bone fractures was inverse for mPC1 (non-essential and essential amino acids, including branched-chain, and bacterial co-metabolites, including isobutyrate, trimethylamines and phenylpropionate, versus fatty acids and VLDL) and mPC4 (HDL), but positive for mPC2 (essential amino acids, including aromatic, and bacterial co-metabolites, including isopropanol and methanol). Findings from BMD models were consistent. Participants with decreased selenium and increased antimony, arsenic and, suggestively, cadmium exposures showed higher mPC2-associated bone fractures risk. Genetic variants annotated to 19 genes, with the strongest evidence for NCF4, NOX4 and XDH, showed differential metabolic-related bone fractures risk. CONCLUSIONS: Metabolic patterns reflecting amino acids, microbiota co-metabolism and lipid metabolism were associated with bone fragility endpoints. Carriers of redox-related variants may benefit from metabolic interventions to prevent the consequences of bone fragility depending on their antimony, arsenic, selenium, and, possibly, cadmium, exposure levels.
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Arsênio , Fraturas Ósseas , Selênio , Humanos , Cádmio , Antimônio , Densidade Óssea/genética , OxirreduçãoRESUMO
Patients with high cholesterol and glucose levels are at high risk for cardiovascular disease. The Sterol Regulatory Element Binding Protein (SREBP) system regulates genes involved in lipid, cholesterol and glucose pathways. Autosomal Dominant Hypercholesterolemias (ADHs) are a group of diseases with increased cholesterol levels. They affect 1 out of every 500 individuals. About 20-30% of patients do not present any mutation in the known genes (LDLR, APOB and PCSK9). ADHs constitute a good model to identify the genes involved in the alteration of lipid levels or possible therapeutic targets. In this paper, we studied whether a mutation in the SREBP system could be responsible for ADH and other metabolic alterations present in these patients. Forty-one ADH patients without mutations in the main responsible genes were screened by direct sequencing of SREBP system genes. A luciferase reporter assay of the found mutation and an oral glucose tolerance test in carriers and non-carriers were performed. We found a novel mutation in the SREBF2 gene that increases transcription levels and cosegregates with hypercholesterolemia, and we found increased glucose levels in one family. SREBP2 is known to be involved in cholesterol synthesis, plasma levels and glucose metabolism in humans. The found mutation may involve the SREBF2 gene in hypercholesterolemia combined with hyperglycemia.
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AIMS: To develop a simple multivariate predictor model of incident type 2 diabetes in general population. METHODS: Participants were recruited from the Spanish Di@bet.es cohort study with 2570 subjects meeting all criteria to be included in the at-risk sample studied here. Information was collected using an interviewer-administered structured questionnaire, followed by physical and clinical examination. CHAID algorithm, which collects the information of individuals with and without type 2 diabetes, was used to develop a decision tree based type 2 diabetes prediction model. RESULTS: 156 individuals were identified as having developed type 2 diabetes (6.5% incidence). Fasting plasma glucose (FPG) at the beginning of the study was the main predictive variable for incident type 2 diabetes: FPG ≤ 92 mg/dL (ref.), 92-106 mg/dL (OR = 3.76, 95%CI = 2.36-6.00), > 106 mg/dL (OR = 13.21; 8.26-21.12). More than 25% of subjects starting follow-up with FPG levels > 106 mg/dL developed type 2 diabetes. When FPG <106 mg/dL, other variables (fasting triglycerides (FTGs), BMI or age) were needed. For levels ≤ 92 mg/dL, higher FTGs levels increased risk of incident type 2 diabetes (FTGs > 180 mg/dL, OR = 14.57; 4.89-43.40) compared with the group of FTGs ≤ 97 mg/dL (FTGs = 97-180 mg/dL, OR = 3.12; 1.05-9.24). This model correctly classified 93.5% of individuals. CONCLUSIONS: The type 2 diabetes prediction model is based on FTGs, FPG, age, gender, and BMI values. Utilizing commonly available clinical data and a simple blood test, a simple tree diagram helps identify subjects at risk of developing type 2 diabetes, even in apparently low risk subjects with normal FPG.
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Diabetes Mellitus Tipo 2 , Glicemia , Estudos de Coortes , Diabetes Mellitus Tipo 2/epidemiologia , Jejum , Humanos , Incidência , Fatores de RiscoRESUMO
BACKGROUND: Limited studies have evaluated the joint influence of redox-related metals and genetic variation on metabolic pathways. We analyzed the association of 11 metals with metabolic patterns, and the interacting role of candidate genetic variants, in 1145 participants from the Hortega Study, a population-based sample from Spain. METHODS: Urine antimony (Sb), arsenic, barium (Ba), cadmium (Cd), chromium (Cr), cobalt (Co), molybdenum (Mo) and vanadium (V), and plasma copper (Cu), selenium (Se) and zinc (Zn) were measured by ICP-MS and AAS, respectively. We summarized 54 plasma metabolites, measured with targeted NMR, by estimating metabolic principal components (mPC). Redox-related SNPs (N = 291) were measured by oligo-ligation assay. RESULTS: In our study, the association with metabolic principal component (mPC) 1 (reflecting non-essential and essential amino acids, including branched chain, and bacterial co-metabolism versus fatty acids and VLDL subclasses) was positive for Se and Zn, but inverse for Cu, arsenobetaine-corrected arsenic (As) and Sb. The association with mPC2 (reflecting essential amino acids, including aromatic, and bacterial co-metabolism) was inverse for Se, Zn and Cd. The association with mPC3 (reflecting LDL subclasses) was positive for Cu, Se and Zn, but inverse for Co. The association for mPC4 (reflecting HDL subclasses) was positive for Sb, but inverse for plasma Zn. These associations were mainly driven by Cu and Sb for mPC1; Se, Zn and Cd for mPC2; Co, Se and Zn for mPC3; and Zn for mPC4. The most SNP-metal interacting genes were NOX1, GSR, GCLC, AGT and REN. Co and Zn showed the highest number of interactions with genetic variants associated to enriched endocrine, cardiovascular and neurological pathways. CONCLUSIONS: Exposures to Co, Cu, Se, Zn, As, Cd and Sb were associated with several metabolic patterns involved in chronic disease. Carriers of redox-related variants may have differential susceptibility to metabolic alterations associated to excessive exposure to metals.
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Arsênio , Metais Pesados , Selênio , Aminoácidos Essenciais , Arsênio/urina , Cádmio , Interação Gene-Ambiente , Humanos , Metais , Metais Pesados/urina , Oxirredução , EspanhaRESUMO
BACKGROUND: Genome assembly of viruses with high mutation rates, such as Norovirus and other RNA viruses, or from metagenome samples, poses a challenge for the scientific community due to the coexistence of several viral quasispecies and strains. Furthermore, there is no standard method for obtaining whole-genome sequences in non-related patients. After polyA RNA isolation and sequencing in eight patients with acute gastroenteritis, we evaluated two de Bruijn graph assemblers (SPAdes and MEGAHIT), combined with four different and common pre-assembly strategies, and compared those yielding whole genome Norovirus contigs. RESULTS: Reference-genome guided strategies with both host and target virus did not present any advantages compared to the assembly of non-filtered data in the case of SPAdes, and in the case of MEGAHIT, only host genome filtering presented improvements. MEGAHIT performed better than SPAdes in most samples, reaching complete genome sequences in most of them for all the strategies employed. Read binning with CD-HIT improved assembly when paired with different analysis strategies, and more notably in the case of SPAdes. CONCLUSIONS: Not all metagenome assemblies are equal and the choice in the workflow depends on the species studied and the prior steps to analysis. We may need different approaches even for samples treated equally due to the presence of high intra host variability. We tested and compared different workflows for the accurate assembly of Norovirus genomes and established their assembly capacities for this purpose.
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Metagenoma , Norovirus , Algoritmos , Benchmarking , Humanos , Metagenômica , Norovirus/genética , Análise de Sequência , Análise de Sequência de DNA , SoftwareRESUMO
Macronutrients represent risk factors for hyperlipidemia or diabetes. Lipid alterations and type 2 diabetes mellitus are global health problems. Overexpression of sterol regulatory element-binding factor (Srebf2) in transgenic animals is linked to elevated cholesterol levels and diabetes development. We investigated the impact of increased Srebf2 locus expression and the effects of control and high-fat, high-sucrose (HFHS) diets on body weight, glucose and lipid metabolisms in transgenic mice (S-mice). Wild type (WT) and S-mice were fed with both diets for 16 weeks. Plasma glucose, insulin and lipids were assessed (n = 25). Immunostainings were performed in liver, pancreas and fat (N = 10). Expression of Ldlr and Hmgcr in liver was performed by RT-PCR (N = 8). Control diet: S-mice showed reduced weight, insulin, total and HDL cholesterol and triglycerides (TG). HFHS diet widened differences in weight, total and HDL cholesterol, insulin and HOMA index but increased TG in S-mice. In S-mice, adipocyte size was lower while HFHS diet produced lower increase, pancreatic ß-cell mass was lower with both diets and Srebf2, Ldlr and Hmgcr mRNA levels were higher while HFHS diet produced a rise in Srebf2 and Hmgcr levels. Srebf2 complete gene overexpression seems to have beneficial effects on metabolic parameters and to protect against HFHS diet effects.
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Glicemia , Colesterol/sangue , Dieta Hiperlipídica/efeitos adversos , Sacarose Alimentar/efeitos adversos , Expressão Gênica , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Animais , Peso Corporal , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Insulina/sangue , Metabolismo dos Lipídeos , Masculino , Camundongos Endogâmicos C57BL , Camundongos TransgênicosRESUMO
OBJECTIVE: To study the association of genes involved in the mitochondrial respiratory chain (MRC) pathway with body mass index (BMI) and obesity risk. DESIGN: This work studies three cross-sectional populations from Spain, representing three provinces: HORTEGA (Valladolid, Northwest/Centre), SEGOVIA (Segovia, Northwest/centre) and PIZARRA (Malaga,South). SETTING: Forty-eight single nucleotide polymorphisms (SNPs) from MRC genes were selected and genotyped by SNPlex method. Association studies with BMI and obesity risk were performed for each population. These associations were then verified by analysis of the studied population as a whole (3731 samples). PARTICIPANTS: A total of 3731 Caucasian individuals: 1502 samples from HORTEGA, 988 from PIZARRA and 1241 from SEGOVIA. RESULTS: rs4600063 (SDHC), rs11205591 (NDUFS5) and rs10891319 (SDHD) SNPs were associated with BMI and obesity risk (p values for BMI were 0.04, 0.0011 and 0.0004, respectively, and for obesity risk, 0.0072, 0.039 and 0.0038). However, associations between rs4600063 and BMI and between these three SNPs and obesity risk are not significant if Bonferroni correction is considered. In addition, rs11205591 and rs10891319 polymorphisms showed an additive interaction with BMI and obesity risk. CONCLUSIONS: Several polymorphisms from genes coding MRC proteins may be involved in BMI variability and could be related to the risk to become obese in the Spanish general population.
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Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , População Branca/genética , Adulto , Idoso , Alelos , Índice de Massa Corporal , Estudos Transversais , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Mitocondriais/genética , Fatores de Risco , EspanhaRESUMO
BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is one of the most devastating malignancies in developed countries because of its very poor prognosis and high mortality rates. By the time PDAC is usually diagnosed only 20-25% of patients are candidates for surgery, and the rate of survival for this cancer is low even when a patient with PDAC does undergo surgery. Lymph node invasion is an extremely bad prognosis factor for this disease. METHODS: We analyzed the mRNA expression profile in 30 PDAC samples from patients with resectable local disease (stages I and II). Neoplastic cells were isolated by laser-microdissection in order to avoid sample 'contamination' by non-tumor cells. Due to important differences in the prognoses of PDAC patients with and without lymph node involvement (stage IIB and stages I-IIA, respectively), we also analyzed the association between the mRNA expression profiles from these groups of patients and their survival. RESULTS: We identified expression profiles associated with patient survival in the whole patient cohort and in each group (stage IIB samples or stage I-IIA samples). Our results indicate that survival-associated genes are different in the groups with and without affected lymph nodes. Survival curves indicate that these expression profiles can help physicians to improve the prognostic classification of patients based on these profiles.
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OBJECTIVES: To investigate the association between IL18RAP and body mass index (BMI) and obesity and to verify the effect of a polymorphism in the microRNA136 (MIR136) IL18RAP binding region. DESIGN: We analysed samples from two Spanish cross-sectional studies, VALCAR (Spanish Mediterranean coast) and Hortega (Spanish centre). These studies aimed at analysing cardiovascular risk and development of cardiovascular disease in the general population. Both populations correspond to regions with different characteristics. SETTING: Five IL18RAP single nucleotide polymorphisms were selected using the SYSNPs web tool and analysed by oligonucleotide ligation assay (SNPlex). For the MIR136 functional study, cells were transfected with plasmids containing different rs7559479 polymorphism alleles and analysed by luciferase reporter assays. PARTICIPANTS: 1970 individuals (Caucasian, both genders): VALCAR (468) and Hortega (1502). RESULTS: rs2293225, rs2272127 and rs7559479 showed the following associations: rs7559479 G allele correlated with a higher obesity risk (P=0.01; OR=1.82; 95% CI 1.15 to 2.87 for the VALCAR group; P=0.033; OR=1.35; 95% CI 1.03 to 1.79 for the Hortega population) and higher body mass index (BMI) values (P=0.0045; P=0.1 for VALCAR and Hortega, respectively); a significant association with obesity (P=0.0024, OR=1.44, 95% CI 1.14 to 1.82) and increased BMI values (P=0.008) was found when considering both populations together. rs2293225 T allele was associated with lower obesity risk (P=0.036; OR=0.60; 95% CI 0.35 to 0.96) and lower BMI values (P=0.0038; OR=1.41) while the rs2272127 G allele was associated with lower obesity risk (P=0.028; OR=0.66; 95% CI 0.44 to 0.97) only in the VALCAR population. A reporter assay showed that the presence of the A allele in rs7559479 was associated with increased MIR136 binding to IL18RAP. CONCLUSIONS: Our results suggest that polymorphisms in IL18RAP influence susceptibility to obesity. We demonstrated that the A allele in rs7559479 increases MIR136 binding, which regulates IL-18 system activity.
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Índice de Massa Corporal , Subunidade beta de Receptor de Interleucina-18/genética , MicroRNAs/genética , Obesidade/genética , Adulto , Idoso , Alelos , Estudos Transversais , Feminino , Predisposição Genética para Doença , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Espanha , População Branca/genéticaAssuntos
Doenças Genéticas Inatas/diagnóstico , Testes Genéticos/métodos , Projetos de Pesquisa , Análise Custo-Benefício , Análise Mutacional de DNA , Doenças Genéticas Inatas/genética , Testes Genéticos/economia , Técnicas de Genotipagem , Humanos , Polimorfismo Conformacional de Fita Simples , Valor Preditivo dos Testes , Kit de Reagentes para DiagnósticoRESUMO
Oxidative stress (OS) has been observed in conditions affecting the cardiovascular system. Familial hypercholesterolemia (FH) is associated with an increased risk of premature coronary heart disease. In the postprandial state, circulating lipids and lipoproteins can modulate OS status. Our aim was to study the response of lymphomonocyte OS status and reactive oxygen species by-products after an oral unsaturated fat load test (OFLT) in those with FH and to compare this response with that obtained in normolipidemic, normoglycemic subjects. We studied 12 patients with FH and 20 healthy controls. In both groups, lymphomonocyte, oxidized/reduced glutathione ratio, and malondialdehyde were determined at baseline and at 2, 4, 6, and 8 hours after an OFLT. Fasting urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine and isoprostane were measured using standard procedures. In both groups, oxidized/reduced glutathione ratio and malondialdehyde significantly decreased in the postprandial state after the OFLT. Both parameters were significantly higher in the FH group at baseline and during all the postprandial points, but the reduction from the baseline levels was significantly higher in the FH group than in the control group. Urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine was significantly increased in the FH group compared with the healthy control group, indicating a higher fasting OS status. We conclude that subjects with FH exhibited OS levels that were higher than in controls before and after an OFLT, but the improvement in the OS status after the unsaturated fat load was significantly higher in subjects with FH.
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Gorduras Insaturadas/farmacologia , Hiperlipoproteinemia Tipo II/diagnóstico , Linfócitos/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Adolescente , Adulto , Idoso , Antioxidantes/metabolismo , Feminino , Glutationa/análise , Dissulfeto de Glutationa/análise , Humanos , Hiperlipoproteinemia Tipo II/sangue , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/urina , Linfócitos/química , Linfócitos/enzimologia , Masculino , Malondialdeído/análise , Pessoa de Meia-Idade , Monócitos/química , Monócitos/enzimologia , Período Pós-PrandialRESUMO
BACKGROUND: Autosomal dominant hypercholesterolemias (ADHs) are characterised by increased plasma levels of total and LDL cholesterol, predisposing to premature atherosclerosis. ADHs comprise several diseases with undistinguishable phenotype, caused by mutations in different genes: LDLR, APOB and PCSK9. Genetic studies are usually performed in patients with altered cholesterol levels. However, some persons carrying pathogenic mutations are normocholesterolemic and there are no further studies about this subject. We have studied the frequency of families and individuals carrying ADH mutations who do not present the disease in Spanish population. METHODS: We have analysed genes known to cause ADH by direct sequencing in 24 ADH families (215 members). Functional effect of some LDLR gene mutations was assessed by transfecting cultured cells with plasmids. RESULTS: Six families with mutations presented 7 mutation carriers who did not show ADH phenotype: 30% of ADH families presented normocholesterolemic individuals, and 7% of carriers of pathogenic mutations did not show ADH phenotype. We have analysed the effect of some of these mutations and they are responsible for impaired LDL receptor function. We have excluded mutations in APOB and PCSK9 genes that could reduce LDLc levels. CONCLUSIONS: An important percentage of ADH families presented individuals who do not show an ADH phenotype, but who are able to transmit the pathogenic mutation to their offspring. Genetic study of all subjects in ADH families should be performed in order to identify normocholesterolemic carriers that allow the detection of mutations in their descendants and the prevention of the disease consequences.
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Apolipoproteína B-100/genética , LDL-Colesterol/genética , Testes Genéticos/métodos , Hiperlipoproteinemia Tipo II/epidemiologia , Hiperlipoproteinemia Tipo II/genética , Mutação , Adolescente , Adulto , Idoso , Animais , Apolipoproteínas B/genética , Células COS , Criança , Chlorocebus aethiops , Saúde da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutagênese , Linhagem , Fenótipo , Pró-Proteína Convertase 9 , Pró-Proteína Convertases/genética , Análise de Sequência de DNA , Serina Endopeptidases/genética , EspanhaRESUMO
Familial hypercholesterolemia (FH) is a clinical condition with high risk for developing atherosclerosis. Increased oxidative stress (OS) and FH have been related to atherosclerosis, but no data are available on levels of OS and antioxidant enzyme activity in circulating mononuclear cells (CMCs) from FH patients. Circulating mononuclear cells are important mediators in atherosclerosis development, and chronically increased blood OS present in FH can induce modification in CMC activity. The objective of the study was to analyze the OS levels in CMCs from FH patients and controls. We have selected 30 nonrelated FH index patients and 30 normoglycemic and normocholesterolemic controls matched by age, sex, body mass index, abdominal circumference, and homeostasis model assessment index. Production of free radicals was analyzed by measurement of xanthine oxidase activity in plasma, reduced and oxidized glutathione (GSH and GSSG, respectively), and malonyldialdehyde in levels CMCs. Antioxidant status was analyzed by measuring antioxidant enzyme activity as superoxide dismutase, catalase, and glutathione peroxidase. We have found that FH patients showed significantly higher xanthine oxidase and malonyldialdehyde enzyme activities, as well as increased GSSG and lower GSH values resulting in a higher GSSG/GSH ratio. These data indicate a higher free radical production in plasma and increased OS levels in CMCs from patients than from controls. No significant differences were found in superoxide dismutase, catalase, and glutathione peroxidase activities between both groups. These data show an important alteration of OS regulation in FH and the absence of antioxidant response in CMCs mediated by some of the major antioxidant enzymes.
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Antioxidantes/análise , Hiperlipoproteinemia Tipo II/sangue , Leucócitos Mononucleares/enzimologia , Estresse Oxidativo , Adulto , Aterosclerose/sangue , Catalase/sangue , Feminino , Glutationa/sangue , Dissulfeto de Glutationa/sangue , Glutationa Peroxidase/sangue , Humanos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Oxirredução , Superóxido Dismutase/sangue , Xantina Oxidase/sangueRESUMO
AIM: to investigate the association of C677T polymorphism in the methylene tetrahydrofolate reductase (MTHFR) gene, homocysteine plasma values (Hcy), and plasma HDL cholesterol in heterozy-gous familial hypercholesterolemia (hFH). METHODS: One hundred and twenty-five hFH subjects were studied. Plasma lipid, lipoprotein, vitamin B12, folic acid and Hcy values were determined. C677T polymorphism in the MTHFR gene was detected by SSCP-PCR. Genetic diagnosis of FH was determined by a three-step protocol using SSCP-PCR, Southern blot, long PCR and automatic sequencing. RESULTS: We found significant differences in plasma HDL-C (CC 1.39+/-0.34, CT 1.33+/-0.39 and TT 1.14+/-0.26 mmol/L, p=0.028) between the C677T MTHFR genotypes, that were also found when gender age, and BMI were included as covariables. In addition, Hcy values were significantly different between C/T MTHFR genotypes (CC 11.75+/-2.9, CT 12.69+/-2.88, TT 15.34+/-2.1 micromol/L). The distribution of gender, smoking habit and LDLR gene mutations was similar among the three groups.A significant correlation was found between Hcy plasma values and plasma HDL-C (-0.370, p= 0.003), but no correlations were found with age, BMI or other lipid and apo B plasma values. CONCLUSION: In hFH subjects, the genotype TT and higher plasma Hcy levels were associated with lower HDL-C plasma values in FH subjects. More studies are needed to confirm our results and also to elucidate the exact mechanism of interaction between plasma homocysteine and lipid metabolism.